Economic production quantity model with learning in production, quality, reliability and energy efficiency

Learning has become essential for many companies whose manufacturing environment, where tasks have increased in complexity, requires a workforce of specific skills. Training of workers and learning-by-doing reduce the unit cost as the production rate speeds and improve product and process quality. Better quality means less rework and machine downtime. All these aspects indirectly influence energy efficiency, which has become a concern for manufacturing companies due to the stringent targets imposed by legislators, the significance of energy costs, and the increasing customers’ awareness about the environment. A company, however, could invest in some alternatives to improve its energy efficiency. This paper, therefore, proposes a lot sizing model for a manufacturing company that includes the relevant learning outcomes, directly and indirectly, affecting its energy efficiency. The main result of the study is to show how learning in production and energy efficiency affects each other and the optimal lot size quantity.